Hubble Sees an Epic Merger of Three Galaxies

A spectacular trio of merging galaxies in the constellation Boötes takes center stage in this image from the NASA/ESA Hubble Space Telescope. These three galaxies are set on a collision course and will eventually merge into a single larger galaxy, distorting one another’s spiral structure through mutual gravitational interaction in the process. An unrelated foreground galaxy appears to float serenely near this scene, and the smudged shapes of much more distant galaxies are visible in the background. Image Credit: ESA/Hubble & NASA, M. Sun

When is 50,000 light-years only a small distance? When three galaxies are that close to one another. At that range, they’re fiercely interacting.

In the case of the three galaxies referred to as SDSSCGB 10189, they’re 50,000 light-years apart and growing closer as they merge into a single massive galaxy.

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The Mass of a Single Star (other than the Sun) has Been Directly Measured for the First Time

How do you measure an object’s weight from a distance? You could guess at its distance and therefore derive its size. Maybe you could further speculate about its density, which would eventually lead to an estimated weight. But these are far from the exact empirical studies that astrophysicists would like to have when trying to understand the weight of stars. Now, for the first time ever, scientists have empirically discovered the weight of a distant single star, and they did so using gravitational lensing.

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Webb Sees Three Galaxy Clusters Coming Together to Form a Megacluster

Pandora's Cluster, imaged by the UNCOVER project using the JWST. Credit: Credits: NASA/ESA/CSA, I. Labbe/R. Bezanson/ Alyssa Pagan (STScI)

As the successor to the venerable Hubble Space Telescope, one of the main duties of the James Webb Space Telescope has been to take deep-field images of iconic cosmic objects and structures. The JWST’s next-generation instruments and improved resolution provide breathtakingly detailed images, allowing astronomers to learn more about the cosmos and the laws that govern it. The latest JWST deep-field is of a region of space known as Abell 7244 – aka. Pandora’s Cluster – where three galaxy clusters are in the process of coming together to form a megacluster.

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It's Time for Mysterious Spokes to Appear in Saturn's Rings

The Hubble Space Telescope captured this image of Saturn in February, 2023. Image Credit: STScI

The Hubble Space Telescope recently captured the appearance of several asymmetrical ‘spokes’ rising above the rings of Saturn, marking a coming change in season for the ringed gas giant. The spokes are made of charged ice particles bulging up and away from the rest of the rings. Researchers aren’t sure exactly what causes the spokes, but they suspect it has something to do with the planet’s powerful magnetic fields.

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Humans Can Still Find Galaxies That Machine Learning Algorithms Miss

Right in the middle of this image lies the newly discovered dwarf galaxy known as Donatiello II, one of three newly discovered galaxies Credit: ESA/Hubble/NASA/B. Mutlu-Pakdil; Acknowledgement: G. Donatiello

The age of big data is upon us, and there are scarcely any fields of scientific research that are not affected. Take astronomy, for example. Thanks to cutting-edge instruments, software, and data-sharing, observatories worldwide are accumulating hundreds of terabytes in a single day and between 100 to 200 Petabytes a year. Once next-generation telescopes become operational, astronomy will likely enter the “exabyte era,” where 1018 bytes (one quintillion) of data are obtained annually. To keep up with this volume, astronomers are turning to machine learning and AI to handle the job of analysis.

While AI plays a growing role in data analysis, there are some instances where citizen astronomers are proving more capable. While examining data collected by the Dark Energy Survey (DES), amateur astronomer Giuseppe Donatiello discovered three faint galaxies that a machine-learning algorithm had apparently missed. These galaxies, all satellites of the Sculptor Galaxy (NGC 253), are now named Donatello II, III, and IV, in his honor. In this day of data-driven research, it’s good to know that sometimes there’s no substitute for human eyeballs and intellect.

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Hubble’s New View of the Tarantula Nebula

A snapshot of the Tarantula Nebula (also known as 30 Doradus) is the most recent Picture of the Week from the NASA/ESA Hubble Space Telescope. Image Credit: ESA/Hubble & NASA, C. Murray, E. Sabbi; Acknowledgment: Y. -H. Chu

The Tarantula Nebula, also called 30 Doradus, is the brightest star-forming region in our part of the galaxy. It’s in the Large Magellanic Cloud (LMC) and contains the most massive and hottest stars we know of. The Tarantula Nebula has been a repeat target for the Hubble since the telescope’s early years.

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Beautiful New Hubble Photo Shows Hot, Young Variable Stars in the Orion Nebula

The bright variable star V 372 Orionis takes centre stage in this image from the Hubble Space Telescope. Credit: ESA/Hubble & NASA, J. Bally, M. Robberto.

Here’s another striking image from the venerable Hubble Space Telescope. These billows of blue and red show a detailed look at a small portion of the famous Orion Nebula. But what really catches the eye are the brilliant stars with the cross-shaped diffraction spikes — a hallmark of Hubble images.

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The JWST is the Shiny New Space Telescope, but the Dependable Hubble is Still Going Strong

The scattered stars of the globular cluster NGC 6355 are strewn across this image from the NASA/ESA Hubble Space Telescope. This globular cluster lies less than 50,000 light-years from Earth in the Ophiuchus constellation. Image Credit: ESA/Hubble & NASA, E. Noyola, R. Cohen

The Venerable Hubble Space Telescope has cemented its place in history. Some call it the most successful science experiment ever. And while the James Webb Space Telescope might vie for that title, the Hubble does things that even the powerful JWST can’t do.

Exhibit A: this stunning image of NGC 6355.

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Wandering Stars Have Been Adrift Between Galaxies for Billions of Years

Hubble Space Telescope images of two massive clusters of galaxies named MOO J1014+0038 (left panel) and SPT-CL J2106-5844 (right panel).. Credits: NASA/ESA/STScI/James Jee (Yonsei University)/Joseph DePasquale (STScI)

In the giant galaxy clusters in the Universe, which can consist of hundreds or thousands of galaxies, there are countless “rogue” stars wandering between them. These stars are not gravitationally bound to any individual galaxy but to the halo of galaxy clusters themselves and are only discernible by the diffuse light they emit – “Ghost Light” or “Intracluster light” (ICL). For astronomers, the explanation for how these stars became so scattered throughout their galaxy clusters has always been an unresolved question.

There are several theories, including the possibility that the stars were pulled from their galaxies, ejected in the course of galactic mergers, or were part of their cluster since its early formation billions of years ago. Using NASA’s Hubble Space Telescope, a team from Yonsei University, Seoul, and the University of California, Davis, conducted an infrared survey of distant galaxy clusters. Their observations suggest that these wandering stars have been adrift for billions of years and were not stripped from their respective galaxies.

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Hubble and Spitzer Team up to Find a Pair of Waterworld Exoplanets

Artist’s impression of a water world, where half of its mass consists of water. Just like our Moon, the planet is bound to its star by tidal forces and always shows the same face to its host star. Credit: Pilar Montañés

As of December 19th, 2022, 5,227 extrasolar planets have been confirmed in 3,908 systems, with over 9,000 more awaiting confirmation. While most of these planets are Jupiter- or Neptune-sized gas giants or rocky planets many times the size of Earth (Super-Earths), a statistically significant number have been planets where water makes up a significant part of their mass fraction – aka. “water worlds.” These planets are unlike anything we’ve seen in the Solar System and raise several questions about planet formation in our galaxy.

In a recent study, an international team led by researchers from the University of Montreal’s Institute for Research on Exoplanets (iREx) found evidence of two water worlds in a single planetary system located about 218 light-years away in the constellation Lyra. Based on their densities, the team determined that these exoplanets (Kepler-138c and Kepler-138d) are lighter than rocky “Earth-like” ones but heavier than gas-dominated ones. The discovery was made using data from NASA’s now-retired Spitzer Space Telescope and the venerable Hubble Space Telescope.

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